The asteroid Kleopatra, like its namesake, the last pharaoh and queen of Egypt, gave birth to twins -- two moons probably spawned by the asteroid sometime in the past 100 million years. Read more
A dog-bone-shaped asteroid's two moons: Kleopatra, Cleoselene, and Alexhelios
Asteroid (216) Kleopatra has been interesting to astronomers for a long time because its brightness is highly variable, but it seems to get more interesting every time somebody looks at it with a new instrument. In 2000 it was found to be "dog-bone" shaped; in 2008 it was discovered to have two moons. This week a paper was published in Icarus by Pascal Descamps, Franck Marchis, and 17 coauthors, who used measurements of the orbits of those moons to determine Kleopatra's mass and density, which revealed that it's 30 to 50% empty space. Read more
The asteroid Kleopatra, like its namesake, the last pharaoh and queen of Egypt, gave birth to twins - two moons probably spawned by the asteroid sometime in the past 100 million years. In the February issue of the journal Icarus, a team of French and American astronomers, including Franck Marchis, a research astronomer at the University of California, Berkeley, and Pascal Descamps, an astronomer at the Institut de Mécanique Céleste et de Calculs des Ephémérides (IMCCE) of the Observatoire de Paris, report the discovery and also confirm earlier reports that the asteroid is shaped like a dog bone. Read more
On September 19, 2008, the asteroid 216 Kleopatra passed close to the Earth at a distance of 186 million kilometres. Astronomers from UC Berkeley carried out the first very high-resolution imaging of this asteroid with the helps of the 10m of Keck telescope in Hawaii. These observations made it possible to identify two tiny moons, of a few kilometres in size, in orbit around Kleopatra. Kleopatra, was nicknamed " the Dog bone" since radar images collected in 2000, showed it was an extremely long main belt asteroid with outgrowths at each end.
The magnitude 9.9 contact binary asteroid (216) Kleopatra is to occult the magnitude 12 star UCAC2 35859936 at 21:02 UT, 17th September, 2008. Kleopatra is a Main belt asteroid, measuring 217 × 94 × 81 km, that was discovered on April 10, 1880 by Johann Palisa. The asteroid is believed to be a metallic rubble pile. The event should be visible from western Africa and Europe.
A movie of an asteroid, made from 23 frames, which were taken over a thirty minute period. This was done by members of Monmouth School and Monmouth Astronomical Research Society (MARS) in the UK. They used the robotic 2m Faulkes Telescope North on the mountain Haleakala, on the Hawaiian island of Maui.
Asteroid Kleopatra can be seen moving slowly against the background of stars. In fact it looks just like one of them and only its motion reveals that it must be much closer to us, orbiting between Mars and Jupiter. Asteroid 216 Kleopatra was discovered in 1880 and is about 200km long and 85km wide. Radar reflections reveal that it is metallic and shaped rather like a dog bone although this cannot be discerned from these images.